BL465c G5 running ESX - VM networking performance issues

This is in the hands of HP and VMware support and on the verge of HP replacing 8 x BL465c G5 servers with 32GB of RAM.

Problem: Virtual Machine networking performance is very poor.

Without going right in to the extensive testing we have completed, I can say with 100% certainty that:

- This is not related to the storage- This is not related to the physical network topology or the configuration of the physical network topology.- The environment works perfectly for BL460c servers under identical conditions.- The condition is present under all versions of VMware tested (3.0.2, 3.0.3, 3.5u1, 3.5u2 and 3.5u2 with all patches)- The condition is not present when running Windows on the same server